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2x^3-x^2+x-2 factorize​

User Rudder
by
3.5k points

2 Answers

9 votes

Solution :

  • 2x³ - x² + x - 2

put x = 1,

  • 2•(1³) - 1² + 1 - 2

  • 2 - 1 + 1 - 2

  • 0

it's value is 0.

hence, it's a solution

divide 2x³ - x² + x - 2 by (x - 1)

  • 2x² + x + 2

it can be written as :

  • (x - 1)(2x² + x + 2)

User Wibbly
by
3.5k points
13 votes

Answer:


(x-1)(2x^2+x+2)

Explanation:

Factorize:


f(x)=2x^3-x^2+x-2

Factor Theorem

If f(a) = 0 for a polynomial then (x - a) is a factor of the polynomial f(x).

Substitute x = 1 into the function:


\implies f(1)=2(1)^3-1^2+1-2=0

Therefore, (x - 1) is a factor.

As the polynomial is cubic:


\implies f(x)=(x-1)(ax^2+bx+c)

Expanding the brackets:


\implies f(x)=ax^3+bx^2+cx-ax^2-bx-c


\implies f(x)=ax^3+(b-a)x^2+(c-b)x-c

Comparing coefficients with the original polynomial:


\implies ax^3=2x^3 \implies a=2


\implies (b-a)x^2=-x^2 \implies b-2=-1 \implies b=1


\implies -c=-2 \implies c=2

Therefore:


\implies f(x)=(x-1)(2x^2+x+2)

Cannot be factored any further.

User Vegar Westerlund
by
3.9k points